Question 15

Highest mark
9.5
Pass rate
97%
Other SAQs in this topic:
Other SAQs in this paper:

With respect to pathological conditions of the spinal cord, for each of the following syndromes, list two causes and the clinical findings:

  • Complete cord transection
  • Cord hemisection
  • Central cord syndrome
  • Anterior cord syndrome (anterior spinal artery syndrome)
  • Cauda Equina syndrome

(You may tabulate your answer.)

(20% marks per syndrome)

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College Answer

Syndrome Aetiology Clinical Findings
Complete Transection Trauma, Infarction, Transverse myelitis, Abscess, Tumour Complete loss of motor and sensory function below level of the lesion
Cord Hemisection Trauma, Tumour, Multiple sclerosis, Abscess Ipsilateral loss of motor and proprioception. Contralateral pain and temperature loss
Central Cord Neck hyperextension, Syringomyelia, Tumour Motor impairment greater in upper limbs than lower Variable sensory loss, bladder dysfunction
Anterior Cord Hyperflexion, Disc protusion, Anterior spinal artery occlusion, Post AAA Motor function impairment, Pain and temperature loss, proprioception spared.
Cauda Equina Disc protusion, Tumour, Infection Bladder/bowel dysfunction Altered sensation in saddle area, sexual dysfunction

Discussion

The Important spinal cord injury syndromes chapter from the Required Reading section contains a table of spinal cord injury syndromes, which is reproduced below to simplify revision.

In brief:

  • The anterior cord contains motor tracts; anterior cord damage results in motor paralysis with preserved sensation.
  • The posterior cord contains predominantly sensory tracts, and damage there will result in predominantly sensory loss, with preserved movement.
  • The lateral cord contains ipsilateral motor/ proprioception  and contralateral pain / temperature fibers. Damage there will leave the damaged side paralysed, and the opposite side anaesthetised.
  • The central cord contains motor fibers from the upper limb (lower limb fibers are more peripheral). Damage there will cause upper limb paralysis.
  • The Cauda Equina governs lower limbs, bladder and bowel. Saddle anaesthesia is the key feature.
Causes and Characteristic Features of Spinal Cord Syndromes

Syndrome

Characteristic features

Causes

There are some causes which are generic for all these syndromes, and they will not be repeated in each box. These are:

  • Trauma
  • Infarction
  • Abscess
  • Tumour or metastatic compression
  • Haematoma
  • AVM/haemorrhage

Any of these can cause any of the spinal syndromes, anywhere. Instead of these, the causes listed below are the characteristic pathological processes which usually give rise to a specific spinal cord syndrome, eg. anterior spinal artery occlusion causing anterior spinal syndrome.

Cord transection
  • Lost bilateral motor
  • Flaccid areflexia
  • Lost bilateral sensory
  • Usually trauma
  • Transverse Myelitis

Cord hemisection
  • Lost ipsilateral motor
  • Lost ipsilateral proprioception and vibration
  • Lost ipsilateral light touch
  • Lost contralateral pain and temperature
  • Penetrating spinal injury
  • Radiation inury
  • Spinal metastases

Anterior cord injury
  • Preserved bilateral proproception, light touch, vibration
  • Lost bilateral pain, temperature, touch
  • Lost bilateral motor control

Interruption of the blood supply to the anterior spinal cord:

  • Aortic dissection
  • IABP complication

Posterior cord injury
  • Lost proprioception,  light touch, vibration
  • Other sensation preserved bilaterally
  • Preserved power bilaterally
  • Ataxia results
  • Hyperextension injury
  • Posterior spinal artery injury
  • Tertiary syphilis
  • Friedrich's ataxia
  • Subacute degeneration (Vitamin B12 deficiency)
  • Atlantoaxial subluxation

Central cord syndrome
  • Sacral sensation preserved
  • Greater weakness in the upper limbs than in the lower limbs.
  • Hyperextension injury with pre-existing canal stenosis
  • Ependymoma
  • Syringomyelia

Conus medullaris syndrome
  • symmetrical paraplegia
  • Mixed upper and lower motor neuron
    findings
  • The same sort of pathologies can give rise either to a cauda equina syndrome or a conus medullaris syndrome; the difference is the level.

Cauda Equina syndrome
  • asymmetrical, lower motor neuron lower limb weakness
  • saddle area paraesthesia
  • bladder and bowel areflexia

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